Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-26T10:58:11.895Z Has data issue: false hasContentIssue false

Natural and monoionic aliettite: hydration and dehydration states

Published online by Cambridge University Press:  09 July 2018

M. F. Brigatti
Affiliation:
Istituto di Mineralogia e Petrologia dell'Universitá, Via S. Eufemia 19, 41100 Modena
L. Poppi
Affiliation:
Istituto di Mineralogia e Petrografia dell'Universitá, Piazza di Porta S. Donato 1, 40127 Bologna, Italy

Abstract

The dehydration of an interstratified talc-trioctahedral smectite mineral (aliettite) from Monte Chiaro, Taro Valley, Italy, saturated by Na, K, Rb, Cs, Mg, Ca, Sr, Ba and NH4 cations, was studied by X-ray powder diffraction and thermal analysis, under different conditions of temperature and relative humidity. Both in the natural and exchanged states the mineral exhibited several orders of basal reflections and, to varying relative humidity (p/po) and temperature (T) conditions, behaved like a smectite except that: (i) the c-dimension was not very sensitive to relative humidity increase; (ii) the closest packing was for T > 400°C, the collapsed state being reached gradually as T increased and an inverse trend was apparent between 20° and 300°C; (iii) the endothermic reactions at T = 400°C and T = 600°C appeared to be affected by the exchange treatment. The experimental data are consistent with a structural model in which it is possible to distinguish layers containing a patchwork of talc and smectite domains: the patchworks are superposed to make a regular alternation of the two domains.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1987

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Alietti, A. (1956) Il minerale a strati misti saponite-talco di Monte Chiaro (Val di Taro, Appennino Emiliano). Rend. Accad. Naz. Lincei 8, 201207.Google Scholar
Alietti, A. & Mejsner, J. (1980) Structure of a talc/saponite mixed-layer mineral. Clays Clay Miner. 28, 388390.CrossRefGoogle Scholar
Bailey, S.W. (1982) Nomenclature for regular interstratifications. Clay Miner. 17, 243248.CrossRefGoogle Scholar
Brigatti, M.F. & Poppi, L. (1985) Interlayer water and swelling properties of natural and homoionic corrensite. Clays Clay Miner. 33, 128134.CrossRefGoogle Scholar
Del Pennino, U., Mazzega, E., Valeri, S., Alietti, A., Brigatti, M.F. & Poppi, L. (1981) Interlayer water and swelling properties of monoionic montmorillonites. J. Colloid Interface Sci. 84, 301309.CrossRefGoogle Scholar
Guenot, B. (1970) Étude d'un minéral argileux du type interstratifié talc-saponite trouvé dans le Précambrian du Congo Kiushasa. Bull, Groupe Fr. Argiles 22, 97104.CrossRefGoogle Scholar
Mackenzie, R.C. (1972) Differential Thermal Analysis. 1. Academic Press, London, 775 pp.Google Scholar
Veniale, F. & Van der Marel, H. W. (1968) A regularly talc-saponite mixed-layer mineral from Ferriere, Nure Valley (Piacenza Province, Italy). Contr. Miner. Petrol. 17, 237254.CrossRefGoogle Scholar
Veniale, F. & Van der Marel, H.W. (1969) Identification of some 1:1 regular interstratified trioctahedral clay minerals. Proc. Int. Clay Conf., Jerusalem, 233244.Google Scholar